Re: MAR24.OBS
Björn Gimle (b_gimle@algonet.se)
Fri, 26 Mar 1999 00:17:45 +0100
>9506601 221540.20 171911+312023 7.1 7.1 0 S
>9506601 221628.48 175639+365325 7.0 7.0 0 S
New observations confirm Mike's orbit, but it is very unusual for a KH,
normally only performing a perigee kick to restore MM 14.82 --> 14.73
and eccentricity 0.048 --> 0.052.
USA 116 elcor
1 23728U 95 66 A 99081.00539165 .00011786 00000-0 28000-3 0 49
2 23728 97.8689 194.7829 0445104 227.3222 128.9687 14.78885467 28503
USA 116 fixed i+e
1 23728U 95 66 A 99081.00517990 .00021270 00000-0 28000-3 0 38
2 23728 97.9280 194.9154 0514316 213.5978 143.1624 14.78858266 28496
Extrapolated 98338
1 23728U 95 66 A 99081.00512390 .00021323 00000-0 28000-3 0 31
2 23728 97.9280 195.0034 0514317 230.4741 124.9941 14.79008929 28495
David's orbit, and my fixed one give a 'reasonable fit' as he wrote.
But I have not been able, with COLA and VEC2TLE, to find a time for
a perigee kick to produce a good fit.
Russell's first(?) night east + near-overhead passes require a lower
apogee (and eccentricity), or a large shift in argument-of perigee.
Mike's orbit is about 40 km higher in perigee and lower in apogee,
but has the perigee in the expected position.
The 197 days without (?) observations make it impossible to compute
the date of the maneuvre, even in a normal case, but if the assumed
drag etc is correct, a possible time is Dec.30 at 19:25, with 6 m/s
alongtrack, -20 m/s radial, to be compared to +11.5 m/s alongtrack to
achieve the more eccentric orbits.
With this low-drag orbit, the standard USA 129 orbit from 99044 would
quickly lose the operational synchronization with USA 116.
If USA 129 has not been observed since Feb.13, it is probable that
it has been moved to a similar orbit, and Feb.14 is actually one of
the possible dates for the change in the USA 116 orbit also.
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